1. Technical Field
The present invention relates to a tubular medical device for insertion into a patient for carrying out a medical procedure. More particularly, the invention relates to a feeding tube having a plurality of external projections along its distal length for facilitating insertion of the feeding tube through the gastrointestinal tract into the jejunum, and including a mechanism for non-traumatic removal of the feeding tube.
2. Background Information
Medical devices intended for non-destructive invasion of body passageways have typically been provided with a low friction external surface. The low friction surface has a slippery texture to facilitate ingress of the device into the body passageway for carrying out a medical procedure, and egress of the device from the body passageway following termination of the procedure. Once inserted, such low friction devices were generally suitable for their intended use. However, the devices were often difficult to deliver and properly position at the desired site. In addition, insertion required a good deal of physician time and effort to insure proper placement.
Recently, as set forth in U.S. Pat. Nos. 6,589,213 and 6,767,339, it was found that the ingress of the medical device or other instrumentation into a desired body site could be facilitated by providing certain projections on the external surface of the device that are engageable with the wall of the body passageway during ingress. The '213 and '339 patents are incorporated by reference herein in their entireties. As disclosed in the incorporated-by-reference patents, the projections are positioned along the device in a manner such that naturally occurring peristaltic contractions grasp the projections along the surface of the device upon insertion, and advance the device toward the target site. Often, such devices comprise feeding tubes for transmission of nutritional products directly into the jejunum of the patient.
When used as jejunal feeding tubes (“J-tubes”) for delivering nutritional products to the jejunum, the feeding tube extends through the esophagus, and thereafter through the stomach and small intestine for delivery to the jejunum. Unlike conventional gastrostomy tubes (“G-tubes”) that are utilized for delivery of nutritional products into the stomach, J-tubes bypass the stomach, and deposit the nutritional products directly into the jejunum (the middle section of the small intestine). Delivery of nutritional products to the jejunum is often preferred to delivery into the stomach, as it decreases the risk of adverse conditions such as gastric reflux and aspiration. In addition, in many cases, direct delivery into the jejunum provides better success in reaching patient nutritional targets, and does so at a more rapid rate than may be achieved with delivery into the stomach with conventional G-tubes.
The device disclosed in the '339 patent employed a series of projections positioned along the external surface of the device. The projections were positioned in a manner such that the surface of the device could be grasped by the peristaltic contractions, and the distal end of the device propelled toward the target site. Self-advancing tubes, such as those described in the '339 patent, are available commercially from Cook Medical, of Bloomington, Ind., and are sold under the trademark TIGER TUBE®. Such tubes have been well received in the medical community, and have been found to achieve a high success rate in post pyloric placement of the feeding tube.
At some point following placement of a self-advancing tube, it will become desirous to remove the tube. Such removal may be desirable, e.g., following completion of the time period within which the nutritional products have been delivered for sustenance of the patient, or when it is desired to replace the tube with another tube. A feeding tube is generally removed by simply withdrawing the tube from the passageway by pulling on the proximal end of the tube. However, the presence of radially-extending projections along the distal length of the tube may impede smooth withdrawal. Although the projections are generally relatively flexible, the presence of such projections may impose an impediment to withdrawal. In addition, some patients may experience various levels of trauma upon withdrawal due to the presence of the outwardly-extending projections.
It would be desirable to provide a tubular medical device, such as a feeding tube, having surface structure suitable for enhancing advancement of the tubular device to the target site by bodily contraction, and including a mechanism for removal of the tubular device from the body passageway with a minimum of trauma to the patient.